KEY to terricolous lichens - italic

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Thallus foliose, homeomerous, dark olive green to brownish black, thick. Lobes 1-
2(3) mm wide, elongate, convex, adpressed to the substratum, very variable in shape,
from radiating to subterete and ascending, flattened or concave. Apothecia frequent,
lecanorine, sessile, up to 3 mm diam. Surface brown to black. Margin distinct, thick,
smooth. Ascospores many-celled, hyaline, ellipsoid, submuriform, 8 per ascus, 17-
26(30) x 8.5-10.5(13) µ. Photobiont cyanobacterial. Excipulum
euthyplectenchymatous. - Note: on more or less calciferous or base-rich soil (e.g. in
dry grasslands), on consolidating sand and terricolous bryophytes, more rarely directly
on rock, often in disturbed habitats such as track sides, also found in large urban
settlements (e.g. in the very center of Rome), certainly the most common species of
the genus in Italy.
Ascospores per ascus 4 10
10 Thallus thick. Lobes convex, ascending
Collema ceraniscum
Thallus foliose, homeomerous, black, thick, lobulate. Lobes 1-2(3) mm wide, convex,
smooth, contiguous, ascending, subterete. Edge lobed. Undersurface black. Apothecia
frequent, lecanorine, sessile, up to 1 mm diam. Surface brown to black. Margin
distinct. Ascospores many-celled, hyaline, ovoid, cubical when young, submuriform,
4 per ascus, 20-36 x 13-22 µ. Photobiont cyanobacterial. Excipulum
euthyplechtenchymatous. – Note: over frost-disturbed ground on weakly calcareous
substrata, a northern species, to be looked for throughout the Alps.
10 Thallus thin. Lobes plane, subcrustose, adpressed to the substratum
Collema limosum
Thallus foliose to subcrustose, homeomerous, black, thin, continuous. Lobes flattened,
contiguous, adpressed to the substratum. Apothecia frequent, lecanorine, sessile, up to
3 mm diam. Surface brown to black. Margin distinct, thick, verruculose. Ascospores
many-celled, hyaline, ellipsoid, submuriform, 4 per ascus, 26-34 x 10-15 µ.
Photobiont cyanobacterial. Excipulum euthyplectenchymatous. - Note: a short-lived
species of mineral, clay soil in disturbed habitats, certainly overlooked, but never
common in Italy.
11 Photobiont chlorococcoid 12
11 Photobiont cyanobacterial 23
12 With soredia
Parmelia sulcata
Thallus foliose, grey, K+ yellow, C-. Lobes (2)3-6 mm wide, elongate, flattened,
adpressed to the substratum, truncated. Edge angular. Pseudocyphellae linear, on
upper surface. Soredia grey. Soralia linear, laminar. Rhizines dark, simple, abundant
at margin. Medulla K+ yellow changing to red, C-, KC+ orange, P+ orange. Medulla
UV -. Apothecia rare, lecanorine, sessile, strongly constricted. Surface brown. Margin
distinct, grey. Ascospores 1-celled, hyaline, ellipsoid, 8 per ascus, 11-15 x 6-8 µ.
Photobiont chlorococcoid. - Note: certainly the most common and wide-ranging
Parmelia in Italy, also present near large urban settlements in the north, rare only in
the eu-Mediterranean belt.
12 Without soredia 13
13 Marginal cilia present
Anaptychia ciliaris
Thallus foliose, grey to grey-brown, bifacial, shrubby, loosely attached, with thin
transparent hairs, K-, C-, P-. Lobes (2)3-6 mm wide, linear, ascending. Edge entire,
with marginal cilia. Undersurface pale brownish to white, channelled. Lower cortex
absent. Apothecia frequent, lecanorine, substipitate, strongly constricted, up to 5 mm
diam. Surface black, often faintly pruinose. Margin distinct, verrucose, grey to grey
brown, smooth or crenulate. Ascospores 2-celled, not hyaline, ellipsoid, constricted at
septa, thin-walled, ornamented, 8 per ascus, 40-45 x 18-24 µ. Pycnidia semiimmersed.
Conidia bacilliform. Photobiont chlorococcoid. - Note: on bark of
deciduous, rarely coniferous, more or less isolated trees, sometimes also on rock and
amongst terricolous mosses in open situations, locally common in the Apennines and
in the islands.
13 Marginal cilia absent 14
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